The average of known samples 9.8, 9.9, x, 10, 10.2 is 10, and the variance is calculated

The average of known samples 9.8, 9.9, x, 10, 10.2 is 10, and the variance is calculated

First calculate the average value, then subtract the average value from each value to get the square of the value, and then add all the items. The variance mainly shows the degree of dispersion
X=15
Variance = 1 + 4 + 1 + 1 + 25 + 0 + 0 + 64 = 96